As known in the art, an "admixture" is a material other than hydraulic cement, water, and aggregates used as an ingredient of concrete or mortar and added to the batch immediately before and during its mixing. Admixtures are used for modifying one or more properties of the concrete in such a way as to make it more suitable for a particular purpose or for economy.
Some of the major reasons for using admixtures are (1) to achieve certain structural improvements in the resulting cured concrete; (2) to improve the quality of concrete through the successive stages of mixing, transporting, placing, and curing during adverse weather or traffic conditions; (3) to overcome certain emergencies during concreting operations; and (4) to reduce the cost of concrete construction. In some instances, the desired result can only be achieved by the use of an admixture. In addition, using an admixture allows the use of less expensive construction methods or designs and thereby offsets the costs of the admixture.
Typically, admixtures are sold as a "finished product" or "finished admixture product" which is shipped in a tanker truck that may have a number of compartments containing other finished admixture products. The terms "finished product" and "finished admixture product" mean that the admixture is comprised of a "raw material" component, such as lignin, corn syrup, an amine, etc. which is either mixed with water and/or another raw material.